#include "sm4.h"  
#include <stdio.h>  
#include <string.h>  

#define SM4_Rotl32(buf, n) (((buf) << n) | ((buf) >> (32 - n)))  

unsigned int SM4_CK[32] = {  
    0x00070e15, 0x1c232a31, 0x383f464d, 0x545b6269,   
    0x70777e85, 0x8c939aa1, 0xa8afb6bd, 0xc4cbd2d9,   
    0xe0e7eef5, 0xfc030a11, 0x181f262d, 0x343b4249,  
    0x50575e65, 0x6c737a81, 0x888f969d, 0xa4abb2b9,   
    0xc0c7ced5, 0xdce3eaf1, 0xf8ff060d, 0x141b2229,   
    0x30373e45, 0x4c535a61, 0x686f767d, 0x848b9299,   
    0xa0a7aeb5, 0xbcc3cad1, 0xd8dfe6ed, 0xf4fb0209,   
    0x10171e25, 0x2c333a41, 0x484f565d, 0x646b7279  
};  

unsigned int SM4_FK[4] = {  
    0xA3B1BAC6, 0x56AA3350, 0x677D9197, 0xB27022DC  
};  

unsigned char SM4_Sbox[256] = {  
    0xd6, 0x90, 0xe9, 0xfe, 0xcc, 0xe1, 0x3d, 0xb7, 0x16, 0xb6, 0x14, 0xc2,  
    0x28, 0xfb, 0x2c, 0x05, 0x2b, 0x67, 0x9a, 0x76, 0x2a, 0xbe, 0x04, 0xc3,  
    0xaa, 0x44, 0x13, 0x26, 0x49, 0x86, 0x06, 0x99, 0x9c, 0x42, 0x50, 0xf4,  
    0x91, 0xef, 0x98, 0x7a, 0x33, 0x54, 0x0b, 0x43, 0xed, 0xcf, 0xac, 0x62,  
    0xe4, 0xb3, 0x1c, 0xa9, 0xc9, 0x08, 0xe8, 0x95, 0x80, 0xdf, 0x94, 0xfa,  
    0x75, 0x8f, 0x3f, 0xa6, 0x47, 0x07, 0xa7, 0xfc, 0xf3, 0x73, 0x17, 0xba,  
    0x83, 0x59, 0x3c, 0x19, 0xe6, 0x85, 0x4f, 0xa8, 0x68, 0x6b, 0x81, 0xb2,  
    0x71, 0x64, 0xda, 0x8b, 0xf8, 0xeb, 0x0f, 0x4b, 0x70, 0x56, 0x9d, 0x35,  
    0x1e, 0x24, 0x0e, 0x5e, 0x63, 0x58, 0xd1, 0xa2, 0x25, 0x22, 0x7c, 0x3b,  
    0x01, 0x21, 0x78, 0x87, 0xd4, 0x00, 0x46, 0x57, 0x9f, 0xd3, 0x27, 0x52,  
    0x4c, 0x36, 0x02, 0xe7, 0xa0, 0xc4, 0xc8, 0x9e, 0xea, 0xbf, 0x8a, 0xd2,  
    0x40, 0xc7, 0x38, 0xb5, 0xa3, 0xf7, 0xf2, 0xce, 0xf9, 0x61, 0x15, 0xa1,  
    0xe0, 0xae, 0x5d, 0xa4, 0x9b, 0x34, 0x1a, 0x55, 0xad, 0x93, 0x32, 0x30,  
    0xf5, 0x8c, 0xb1, 0xe3, 0x1d, 0xf6, 0xe2, 0x2e, 0x82, 0x66, 0xca, 0x60,  
    0xc0, 0x29, 0x23, 0xab, 0x0d, 0x53, 0x4e, 0x6f, 0xd5, 0xdb, 0x37, 0x45,  
    0xde, 0xfd, 0x8e, 0x2f, 0x03, 0xff, 0x6a, 0x72, 0x6d, 0x6c, 0x5b, 0x51,  
    0x8d, 0x1b, 0xaf, 0x92, 0xbb, 0xdd, 0xbc, 0x7f, 0x11, 0xd9, 0x5c, 0x41,  
    0x1f, 0x10, 0x5a, 0xd8, 0x0a, 0xc1, 0x31, 0x88, 0xa5, 0xcd, 0x7b, 0xbd,  
    0x2d, 0x74, 0xd0, 0x12, 0xb8, 0xe5, 0xb4, 0xb0, 0x89, 0x69, 0x97, 0x4a,  
    0x0c, 0x96, 0x77, 0x7e, 0x65, 0xb9, 0xf1, 0x09, 0xc5, 0x6e, 0xc6, 0x84,  
    0x18, 0xf0, 0x7d, 0xec, 0x3a, 0xdc, 0x4d, 0x20, 0x79, 0xee, 0x5f, 0x3e,  
    0xd7, 0xcb, 0x39, 0x48  
};  

void SM4_KeySchedule(unsigned char MK[], unsigned int rk[])   
{   
    unsigned int tmp, buf, K[36];  
    int i;  
    
    for (i = 0; i < 4; i++) {  
        K[i] = SM4_FK[i] ^ (  
            (MK[4 * i] << 24) |   
            (MK[4 * i + 1] << 16) |   
            (MK[4 * i + 2] << 8) |   
            (MK[4 * i + 3])  
        );  
    }  
    
    for (i = 0; i < 32; i++) {  
        tmp = K[i + 1] ^ K[i + 2] ^ K[i + 3] ^ SM4_CK[i];  
        
        // 非线性操作  
        buf = (SM4_Sbox[(tmp >> 24) & 0xFF] << 24) |  
              (SM4_Sbox[(tmp >> 16) & 0xFF] << 16) |  
              (SM4_Sbox[(tmp >> 8) & 0xFF] << 8) |  
              (SM4_Sbox[tmp & 0xFF]);  
        
        // 线性操作  
        K[i + 4] = K[i] ^ (buf ^ SM4_Rotl32(buf, 13) ^ SM4_Rotl32(buf, 23));  
        rk[i] = K[i + 4];  
    }  
}  

void SM4_Encrypt(unsigned char MK[], unsigned char PlainText[], unsigned char CipherText[])   
{   
    unsigned int rk[32], X[36], tmp, buf;  
    int i, j;  
    
    SM4_KeySchedule(MK, rk);  
    
    for (j = 0; j < 4; j++) {  
        X[j] = (PlainText[j * 4] << 24) |   
               (PlainText[j * 4 + 1] << 16) |   
               (PlainText[j * 4 + 2] << 8) |   
               (PlainText[j * 4 + 3]);  
    }  
    
    for (i = 0; i < 32; i++) {  
        tmp = X[i + 1] ^ X[i + 2] ^ X[i + 3] ^ rk[i];  
        
        // 非线性操作  
        buf = (SM4_Sbox[(tmp >> 24) & 0xFF] << 24) |  
              (SM4_Sbox[(tmp >> 16) & 0xFF] << 16) |  
              (SM4_Sbox[(tmp >> 8) & 0xFF] << 8) |  
              (SM4_Sbox[tmp & 0xFF]);  
        
        // 线性操作  
        X[i + 4] = X[i] ^ (buf ^ SM4_Rotl32(buf, 2) ^ SM4_Rotl32(buf, 10)   
                             ^ SM4_Rotl32(buf, 18) ^ SM4_Rotl32(buf, 24));  
    }  
    
    for (j = 0; j < 4; j++) {  
        CipherText[4 * j]     = (X[35 - j] >> 24) & 0xFF;  
        CipherText[4 * j + 1] = (X[35 - j] >> 16) & 0xFF;  
        CipherText[4 * j + 2] = (X[35 - j] >> 8) & 0xFF;  
        CipherText[4 * j + 3] = (X[35 - j]) & 0xFF;  
    }  
}  

void SM4_Decrypt(unsigned char MK[], unsigned char CipherText[], unsigned char PlainText[])   
{   
    unsigned int rk[32], X[36], tmp, buf;  
    int i, j;  
    
    SM4_KeySchedule(MK, rk);  
    
    for (j = 0; j < 4; j++) {  
        X[j] = (CipherText[j * 4] << 24) |   
               (CipherText[j * 4 + 1] << 16) |   
               (CipherText[j * 4 + 2] << 8) |   
               (CipherText[j * 4 + 3]);  
    }  
    
    for (i = 0; i < 32; i++) {  
        tmp = X[i + 1] ^ X[i + 2] ^ X[i + 3] ^ rk[31 - i];  
        
        // 非线性操作  
        buf = (SM4_Sbox[(tmp >> 24) & 0xFF] << 24) |  
              (SM4_Sbox[(tmp >> 16) & 0xFF] << 16) |  
              (SM4_Sbox[(tmp >> 8) & 0xFF] << 8) |  
              (SM4_Sbox[tmp & 0xFF]);  
        
        // 线性操作  
        X[i + 4] = X[i] ^ (buf ^ SM4_Rotl32(buf, 2) ^ SM4_Rotl32(buf, 10)   
                             ^ SM4_Rotl32(buf, 18) ^ SM4_Rotl32(buf, 24));  
    }  
    
    for (j = 0; j < 4; j++) {  
        PlainText[4 * j]     = (X[35 - j] >> 24) & 0xFF;  
        PlainText[4 * j + 1] = (X[35 - j] >> 16) & 0xFF;  
        PlainText[4 * j + 2] = (X[35 - j] >> 8) & 0xFF;  
        PlainText[4 * j + 3] = (X[35 - j]) & 0xFF;  
    }  
}  

int SM4_SelfCheck()   
{   
    int i;  
    
    // 标准数据  
    unsigned char key[16] = {  
        0x01, 0x23, 0x45, 0x67,   
        0x89, 0xab, 0xcd, 0xef,   
        0xfe, 0xdc, 0xba, 0x98,  
        0x76, 0x54, 0x32, 0x10  
    };  
    
    unsigned char plain[16] = {  
        0x01, 0x23, 0x45, 0x67,   
        0x89, 0xab, 0xcd, 0xef,   
        0xfe, 0xdc, 0xba, 0x98,  
        0x76, 0x54, 0x32, 0x10  
    };  
    
    unsigned char cipher[16] = {  
        0x68, 0x1e, 0xdf, 0x34,   
        0xd2, 0x06, 0x96, 0x5e,   
        0x86, 0xb3, 0xe9, 0x4f,  
        0x53, 0x6e, 0x42, 0x46  
    };  
    
    unsigned char En_output[16];  
    unsigned char De_output[16];  
    
    SM4_Encrypt(key, plain, En_output);  
    SM4_Decrypt(key, cipher, De_output);  
    
    for (i = 0; i < 16; i++) {  
        if ((En_output[i] != cipher[i]) || (De_output[i] != plain[i])) {  
            printf("Self-check error\n");  
            return 1;  
        }  
    }  
    
    printf("sm4(16字节)自检成功\n\n");  
    return 0;  
}  

void sm4ecb(unsigned char *in, unsigned char *out, unsigned int length, unsigned char *key, unsigned int enc)   
{   
    unsigned int len = length;  
    
    if ((in == NULL) || (out == NULL) || (key == NULL) || (length % SM4_BLOCK_SIZE != 0))  
        return;  
    
    if ((SM4_ENCRYPT != enc) && (SM4_DECRYPT != enc))  
        return;  
    
    while (len >= SM4_BLOCK_SIZE) {  
        if (SM4_ENCRYPT == enc)  
            SM4_Encrypt(key, in, out);  
        else  
            SM4_Decrypt(key, in, out);  
        
        len -= SM4_BLOCK_SIZE;  
        in += SM4_BLOCK_SIZE;  
        out += SM4_BLOCK_SIZE;  
    }  
}  

void sm4cbc(unsigned char *in, unsigned char *out, unsigned int length, unsigned char *key, unsigned char *ivec, unsigned int enc)   
{   
    unsigned int n;  
    unsigned int len = length;  
    unsigned char tmp[SM4_BLOCK_SIZE];  
    const unsigned char *iv = ivec;  
    unsigned char iv_tmp[SM4_BLOCK_SIZE];  
    
    if ((in == NULL) || (out == NULL) || (key == NULL) || (ivec == NULL) || (length % SM4_BLOCK_SIZE != 0))  
        return;  
    
    if ((SM4_ENCRYPT != enc) && (SM4_DECRYPT != enc))  
        return;  
    
    if (SM4_ENCRYPT == enc) {  
        while (len >= SM4_BLOCK_SIZE) {  
            for (n = 0; n < SM4_BLOCK_SIZE; ++n)  
                out[n] = in[n] ^ iv[n];  
            
            SM4_Encrypt(key, out, out);  
            iv = out;  
            len -= SM4_BLOCK_SIZE;  
            in += SM4_BLOCK_SIZE;  
            out += SM4_BLOCK_SIZE;  
        }  
    }  
    else if (in != out) {  
        while (len >= SM4_BLOCK_SIZE) {  
            SM4_Decrypt(key, in, out);  
            for (n = 0; n < SM4_BLOCK_SIZE; ++n)  
                out[n] ^= iv[n];  
            
            iv = in;  
            len -= SM4_BLOCK_SIZE;  
            in += SM4_BLOCK_SIZE;  
            out += SM4_BLOCK_SIZE;  
        }  
    }  
    else {  
        memcpy(iv_tmp, ivec, SM4_BLOCK_SIZE);  
        while (len >= SM4_BLOCK_SIZE) {  
            memcpy(tmp, in, SM4_BLOCK_SIZE);  
            SM4_Decrypt(key, in, out);  
            for (n = 0; n < SM4_BLOCK_SIZE; ++n)  
                out[n] ^= iv_tmp[n];  
            memcpy(iv_tmp, tmp, SM4_BLOCK_SIZE);  
            
            len -= SM4_BLOCK_SIZE;  
            in += SM4_BLOCK_SIZE;  
            out += SM4_BLOCK_SIZE;  
        }  
    }  
}  

void sm4cfb(const unsigned char *in, unsigned char *out, const unsigned int length, unsigned char *key, const unsigned char *ivec, const unsigned int enc)   
{   
    unsigned int n = 0;  
    unsigned int l = length;  
    unsigned char c;  
    unsigned char iv[SM4_BLOCK_SIZE];  
    
    if ((in == NULL) || (out == NULL) || (key == NULL) || (ivec == NULL))  
        return;  
    
    if ((SM4_ENCRYPT != enc) && (SM4_DECRYPT != enc))  
        return;  
    
    memcpy(iv, ivec, SM4_BLOCK_SIZE);  
    
    if (enc == SM4_ENCRYPT) {  
        while (l--) {  
            if (n == 0) {  
                SM4_Encrypt(key, iv, iv);  
            }  
            
            iv[n] = *(out++) = *(in++) ^ iv[n];  
            n = (n + 1) % SM4_BLOCK_SIZE;  
        }  
    }  
    else {  
        while (l--) {  
            if (n == 0) {  
                SM4_Encrypt(key, iv, iv);  
            }  
            
            c = *(in);  
            *(out++) = *(in++) ^ iv[n];  
            iv[n] = c;  
            n = (n + 1) % SM4_BLOCK_SIZE;  
        }  
    }  
}  

void sm4ofb(const unsigned char *in, unsigned char *out, const unsigned int length, unsigned char *key, const unsigned char *ivec)   
{   
    unsigned int n = 0;  
    unsigned int l = length;  
    unsigned char iv[SM4_BLOCK_SIZE];  
    
    if ((in == NULL) || (out == NULL) || (key == NULL) || (ivec == NULL))  
        return;  
    
    memcpy(iv, ivec, SM4_BLOCK_SIZE);  
    
    while (l--) {  
        if (n == 0) {  
            SM4_Encrypt(key, iv, iv);  
        }  
        
        *(out++) = *(in++) ^ iv[n];  
        n = (n + 1) % SM4_BLOCK_SIZE;  
    }  
}